At the time of fast charging of an electric vehicle, power which is consumed at the time of traveling of the electric vehicle should be supplied in a comparatively short charging time. In other words, a large load is applied to a so-called system power supply, that is, a power facility which supplies commercial power, in inverse proportion to the shortness of the charging time of the electric vehicle.
In addition, since the time zone during which fast charging of the electric vehicle is required depends on the life pattern of a driver, hereafter, if the electric vehicles become more popular, fast charging may be intensively performed according to the season, a day of the week, a time zone, or the like. Accordingly, controlling smoothing power demand for a short period of time due to fast charging and limiting the power demand peak for a system power supply is required.
As a method therefor, a technique in which each of a plurality of devices including a power generation device, such as a solar power generation device, or a storage device, such as a fixed storage battery, in addition to the system power supply are used in combination is known.
In relation to the above, PTL 1 (WO2011/162025) discloses a technique relating to a DC power distribution system. The DC power distribution system described in PTL 1 includes a DC power distribution system, a first power conversion device, a second power conversion device, and a third power conversion device. The DC power distribution system supplies DC power to a load device. The first power conversion device performs voltage conversion of generated power of a solar power generation device and supplies power to the DC power distribution system. The second power conversion device performs voltage conversion between a first power storage device always connected to the DC power distribution system and the DC power distribution system, and supplies power from one side to the other side. The third power conversion device performs power conversion between an AC system and the DC power distribution system, and supplies power from one side to the other side. The DC power distribution system includes an operation mode setting unit and an operation control unit. The operation mode setting unit determines an operation mode according to operation mode determination information for setting an operation mode of the DC power distribution system. The operation control unit sets a first control parameter for the second power conversion device and a second control parameter for the third power conversion device according to the operation mode set by the operation mode setting unit. The second power conversion device performs control of a power supply direction, operation start, and operation stop according to the voltage of the DC power distribution system and the first control parameter. The third power conversion device performs control of a power supply direction, operation start, and operation stop according to the voltage of the DC power distribution system and the second control parameter.
In the DC power distribution system described in PTL 1, first, a storage device of a charging facility is charged with power supplied from a plurality of power supply devices, and then, power charged in the storage device is discharged to charge the electric vehicle. For this end, it is necessary to appropriately control the timing at which the storage device is charged or discharged, the timing at which a plurality of power supply devices, such as a system power supply or a power generation device, supply power to a storage battery, or the like.